The Federal Circuit’s recent decision in Range of Motion Products, LLC v. Armaid Company Inc. highlights a growing dissatisfaction with courts’ broad use of the sufficiently distinct/plainly dissimilar standard to dispose of design patent infringement cases at summary judgment. Courts have been using it to deem an accused product “plainly dissimilar” from the patented design—and thus non-infringing—even when the product looks similar, taking the infringement question away from the jury. A strong dissent by Chief Judge Moore appears to advocate doing away with this standard altogether, portending further challenges and possible future changes.
A U.S. design patent protects a product’s appearance. To evaluate whether a product infringes a design patent, courts apply the “ordinary observer” test to determine if the product’s appearance is “substantially the same” as the patented design. This comes from an 1871 Supreme Court case, Gorham v White.[1]
Generally, infringement is a question for the fact-finder (e.g., a jury) to decide.[2] But in 2008, the Federal Circuit introduced a shortcut: if the claimed design and accused product are “sufficiently distinct” and “plainly dissimilar” courts may find that the patent owner failed to prove infringement as a matter of law, taking the case out of the fact finder’s hands on summary judgment.[3]
Applying the “Plainly Dissimilar” Test
In Range of Motion Products, LLC v. Armaid Company Inc., the Federal Circuit affirmed summary judgment upholding non-infringement because the asserted design for a body massaging apparatus and the accused product were plainly dissimilar.[4]
The court first addressed claim scope in light of functional components, before turning to the “ordinary observer test.” The Federal Circuit summarized differences identified by the district court and based on those differences, held the district court did not err in determining that the ’155 patent design and the Armaid design were plainly dissimilar, effectively taking the infringement determination away from a jury.[5]
A Call To Eliminate the “Plainly Dissimilar” Test
In dissent, Judge Moore contends that Federal Circuit precedent in Egyptian Goddess incorrectly altered the frame of reference for evaluating infringement from “substantially similar” to “plainly dissimilar.”[6]
In Egyptian Goddess, the Federal Circuit eliminated the addition of a “point of novelty” inquiry to the longstanding “substantial similarity” test.[7] Under the point of novelty test, no matter how similar two designs look, infringement required that the accused device “appropriate the novelty in the patented device which distinguishes it from the prior art.”[8] The Egyptian Goddess decision reaffirmed that the ordinary observer test is the sole test for determining infringement, and concluded that infringement should be evaluated in the context of the prior art. But it introduced an exception: if the patented design and accused product are “sufficiently distinct” or “plainly dissimilar,” then the prior art need not be considered.[9] This exception created the summary judgment standard at issue.
Relying on amicus briefs, “spot the difference” puzzles, AI search results, surveys, Supreme Court precedent, and psychological literature, Judge Moore emphasizes the practical impact of seeking out differences instead of evaluating similarity.[10] Focusing on differences makes it more likely that two designs are found substantially distinct or plainly dissimilar and focusing on similarity makes it more likely that two designs are found substantially similar. “In short, framing matters and can meaningfully impact outcome.”[11]
Highlights for Children, Oct. 2016, at 20, available at https://fliphtml5.com/fwspv/ktmi.
Judge Moore also highlights recent Federal Circuit cases that may have been incorrectly decided by applying the “plainly dissimilar” test.[12] For example, reviewing the court’s decision in North Star[13] to affirm summary judgment of noninfringement, Judge Moore reasons:
It is hard for me to look at the patented pool design and the accused product and agree that no reasonable juror could find that their overall appearance is substantially similar. Here too, could the framing “plainly dissimilar” rather than “substantially similar” have impacted the outcome?[14]
Judge Moore concludes “I think we ought to correct our error in Egyptian Goddess and reaffirm that the substantially similar test, announced by the Supreme Court in Gorham, is ‘the sole test.’”[15] The majority, however, contends Judge Moore fails to properly consider the impact that functional aspects of the design have on claim construction and therefore seeks to improperly extend the patent’s scope.[16]
This dispute may set the stage for an en banc hearing and will likely attract several amicus briefs. The final decision may alter the dynamic between design patent owners and defendants. While defendants have leveraged the “plainly dissimilar” test to dispose of infringement claims without reaching a jury, a decision reaffirming that the “substantially similar” test is the sole test for evaluating design patent infringement would be a welcome change for patent owners and would allow more infringement determinations to be considered on their merits by a jury.
[1] 81 U.S. 511 (1871)
[2] Columbia Sportswear N. Am., Inc. v. Seirus Innovative Accessories, Inc., 942 F.3d 1119, 1129 (Fed. Cir. 2019).
[3] Egyptian Goddess, Inc. v. Swisa, Inc., 543 F.3d 665, 670 (Fed. Cir. 2008)
[4] Range of Motion Products, LLC v. Armaid Company Inc., No. 23-2427, slip op. at 11-15 (Fed. Cir. Feb. 2, 2026)
[5] Id. at 15.
[6] Id. at 20 (Moore, Dissenting).
[7] Egyptian Goddess, 543 F.3d at 670-72, 678.
[8] Litton Systems, Inc. v. Whirlpool Corporation, 728 F.2d 1423, 1444 (Fed. Cir. 1984).
[9] Egyptian Goddess, 543 F.3d at 678.
[10] Range of Motion Products, No. 23-2427, slip op. at 21-23 (Moore, Dissenting).
[11] Id. at 23 (Moore, Dissenting).
[12] Id. at 24-26 (Moore, Dissenting).
[13] North Star Tech. Int’l Ltd. v. Latham Pool Prods., Inc., No. 23-2138, 2025 WL 1189919, at *1–2 (Fed. Cir. Apr. 24, 2025).
[14] Range of Motion Products, No. 23-2427, slip op. at 25 (Moore, Dissenting)
[15] Id. at 26 (Moore, Dissenting).
[16] Id. at 13.
